This question already has answers here:
When to use single quotes, double quotes, and backticks in MySQL
(13 answers)
Closed 2 years ago.
I am working on a project where another developer created a table with column names like 'Business Name'. That is a space between two words. If I run a SELECT statement with 'Business Name' it says there is no column with name 'Business'.
How can I solve this problem?
Generally the first step is to not do that in the first place, but if this is already done, then you need to resort to properly quoting your column names:
SELECT `Business Name` FROM annoying_table
Usually these sorts of things are created by people who have used something like Microsoft Access and always use a GUI to do their thing.
If double quotes does not work , try including the string within square brackets.
For eg:
SELECT "Business Name","Other Name" FROM your_Table
can be changed as
SELECT [Business Name],[Other Name] FROM your_Table
You need to use backtick instead of single quotes:
Single quote - 'Business Name' - Wrong
Backtick - `Business Name` - Correct
To each his own but the right way to code this is to rename the columns inserting underscore so there are no gaps. This will ensure zero errors when coding. When printing the column names for public display you could search-and-replace to replace the underscore with a space.
I got here with an MS Access problem.
Backticks are good for MySQL, but they create weird errors, like "Invalid Query Name: Query1" in MS Access, for MS Access only, use square brackets:
It should look like this
SELECT Customer.[Customer ID], Customer.[Full Name] ...
I think double quotes works too:
SELECT "Business Name","Other Name" FROM your_Table
But I only tested on SQL Server NOT mySQL in case someone work with MS SQL Server.
Related
This question already has answers here:
When to use single quotes, double quotes, and backticks in MySQL
(13 answers)
Closed 4 months ago.
This line of code is no working, and I cannot for the life of me figure out what is wrong with it.
INSERT INTO teacher (email,password,admin) VALUES (deborah68#example.org,d%6AsQPq7y,1);
this wont run and says the error is near the end of the line
any help is appreciated, the schema is called at3
Why are you not enclosing the string/char data in single quotes ? Assuming they are of datatype varchar, you simply enclose them in single quotes and the command will work.
INSERT INTO teacher (email,password,admin) VALUES ('deborah68#example.org','d%6AsQPq7y',1)
Assuming your email and password are datatype of varchar, try putting '' between the values, or better you can use parameterized value if it's any backend code, try:
INSERT INTO teacher (email,password,admin) VALUES ('deborah68#example.org','d%6AsQPq7y',1);
I have been working on a database for my coursework and have used phpMyAdmin to build it. Now I am working on the queries using the query tool.
When I pick the tables and data I want to query and press "update query" it will generate the query which looks something like this:
SELECT `Customer`.`CustomerName`, `OrderDetails`.`Product`, `OrderDetails`.`QuantityOrdered`
FROM `Customer`
LEFT JOIN `Order` ON `Order`.`Customer` = `Customer`.`CustomerID`
LEFT JOIN `OrderDetails` ON `OrderDetails`.`Order` = `Order`.`OrderID`
This works fine and gives me the results I was expecting. However when I try and write my own query and put something like "SELECT Customer.CustomerName," WITHOUT the ' symbol it won't work and just throws up an error message.
Must I always wrap them using the ' symbol for the query to work?
Forward quotes are used to escape object names in MySQL. You don't have to use them unless you use names that wouldn't be valid identifiers - in this case, the table name order is a reserved word, and must be escaped. All the other tables and columns you're using seem to be OK.
Except for the visual nightmare and ability to create horrendous table names, backticks are entirely unnecessary. You will, however, be required to wrap any variables in single quotes.
As you can see from my example below, using backticks is not a requirement with PHPMYADMIN;
The reason it is not working when you remove the backticks is because you have a column called 'order'. Order is a keyword in SQL and therefore cannot be used as a column name without being wrapped in either quotes or backticks.
This question already has answers here:
character for single quote
(1 answer)
Syntax error due to using a reserved word as a table or column name in MySQL
(1 answer)
Closed 8 years ago.
hey guys was hoping you could help me out,
Not sure if I always had this problem or if its new, in phpmyadmin in the sql tab, the apostrophe it recognizes is different from what i type, for example,
when i type, it is
SELECT * FROM 'table'
this gives me an error, so instead I have to like copy/paste the inverted commas of some prebuilt query so that it looks like
SELECT * FROM `table`
see how the apostrophes are different? any way I can fix this?
also, i have seen many queries on the web, and i think even queries i call from php dont require table names to have apostrophes. But when write it in phpmyadmin, I can do queries without table names having apostrophes?
thanks in advance.
In MYSQL, table is a reserved keyword. If you want to use reserved keywords in mysql in query, you have to enclose them in backtick(`).
As table is reserved keyword you query should be
SELECT * FROM `table`
Regarding single quote ('), in mysql, it represents string value.
SELECT *, 'table' FROM `table`;
Demo
You should only need to quote table names when they conflict with a reserved word.
Also:
` = Grave accent, or (because someone needed to invent a word) backtick
' = Apostrophe, or straight single quote
You dont need apostrophe on table name.
You should use ` in cases that your table/field name is a reserve word eg:
SELECT `distinct`, myfields FROM mytable
note that distinct is an sql command so you need to put the `.
SELECT * FROM `table`
table here should be inside `.
There are two different characters, the backtick and the single quote. Table and column names can be surrounded by the backtick, strings can be surrounded by quotes. There is nothign to fix :D
In a statement like this;
$sql = "SELECT distinct `term`,count(*) as count
FROM {$temp_table_name}
group by `term` order by count DESC";
What does using the back tick character (`) around the field name 'term' buy me?
Is the usage of back ticks for performance reasons? Or is it for some sort of a SQL injection protection?
Note: After I submit the question, I realized that the backtick character does not show around the field name 'term' - right here on stackoverflow.
I don't know of a way of making it appear here in the question body.
If term is mysql key word, you need to quote it by `, otherwise, it is not necessary.
Ps: distinct is not necessary in your case, because you group by it.
The back-tick is the 'official' identifier quote character.
http://dev.mysql.com/doc/refman/5.0/en/identifiers.html
It allows a wider array of characters in an identifier, as described on the linked documentation.
Backticks just allow the use of spaces or other alternate characters in field names.
I think it's already been pretty well explained here.
When We use a keyword as a table name,field-name in MySQL use backticks, or double-quotes when ANSI_QUOTES is enabled.Other wise it is not necessary.It is not releated to SQL injection protection
I want to select my particular database in mysql console, but the problem is that my database name has a space in between and mysql ignores the part after the space. For instance, when i give the command:
use 'student registration'
I get the message:
cannot find database 'student'
You should try using back ticks ("`") to quote your database name. Generally speaking, it's probably better to use a naming convention to eliminate white space, e.g.
USE `StudentRegistration`;
or
USE `student_registration`;
You have two options.
1 Enclose the database name in backticks or single quotes.
USE `student registration`;
USE 'student registration';
2 Escape the white space character.
USE student\ registration;
Oddly enough this produces.
ERROR: Unknown command '\ '.
But still changes the database.
When I had to deal with other people's tables with spaces the following worked:
use `student registration`;
At least that would be yours.
Use Double quotes instead of single, double quotes worked for me :
USE "student registration";
Use student registration without quotes.
You have to use square brackets to get this work:
Use [student registration]